Controlling system for electric elevators.



No. 704,337. Y Patented July 8, I902.

.1. u. IHLDER.

CONTROLLING SYSTEM FOR ELECTBIG ELEVATORS.

(Application filed Jan. 11, 1902.)

(No Model.)

m: wmim Hams ca. PHOTO-HTHQ, \vasummm u c UNITED STATES PATENT OEEIcE.

JOHN D. II'ILDER, OF YONKERS, NEW YORK, ASSIGNOR TO OTIS ELEVATOR COMPANY, OF EAST ORANGE, NEIV JERSEY, A CORPORATION OF NEIV JERSEY.

CONTROLLING SYSTEM FOR ELECTRIC ELEVATORS.

SPECIFICATION forming part of Letters Patent N 0. 704,337, dated July 8, 1902.

' Application filed January 11, 1902. Serial No. 89,341. (No model.)

To all whom, it rim/y concern: stations, of which there may be any desirable Be it known that 1, JOHN D. IHLDER, a citinumber, four being shown in this instance, zen of the United States, residing at Yonkers, and means are provided at the stations, as in the county of VVestchester and State of they may also be provided upon the car, so New York, have invented certain new and connected with the motor that its operation 55 useful Improvements in Controlling Systems is controllable from a floor or station or from for Electric Elevators, of which the following the car. is a specification. v The particular motor-controlling apparatus My invention has reference in general to shown and to be described operates upon the the operation of machinery, but more particsame general principles as the apparatus 60 ularly to its operation by electric power. shown and described in my previous applica- While my invention is applicable to many tion, Serial No. (560,873, filed December 6, classes of apparatus, it is particularly appli- 1897, entitled Electric operation of elevators cable to elevators operated by electric motors by single push-button system, wherein the in which a controlling-circuit for the motor is manipulation of the switch or push-button at 65 led to the several floors or stations and to the the station or corresponding push-button on car; and my invention has for its object to the carwillset the motorin operation to bring obviate the necessity of operating with a high the car to the floor corresponding to the switch potential in the controlling-circuit. or push-button manipulated, where it will be My invention consists, primarily, in appaautomatically stopped, while interference 7o ratus for controlling motors provided with a with the operation of the motor from any controlling-circuit of lower potential than the other floor is prevented until the car reaches main circuit and so arranged that afterithas its destination. I am not to be understood, been energized to operate the motoritis autohowever, as limiting my invention to this matically renderedinoperative during the opparticular controlling apparatus for motors, eration of the motor. but have simply shown it in the connection My invention also consists in motor-condescribed as illustrative of one of its many trolling apparatus provided with separate applications. controlling-circuits of different potentials re- In controlling apparatus for elevators of 30 ciprocally controlling each other, one conthe class described itis customary to lead the trolling-circuit being preferably derived from controlling-circuit to the floors or stations as the main line, while another may be derived a shunt from the supply-line, in which case from a separate source oflowerpotential than the electric potential of the controlling-cirthe main line. cuit is substantially the same as that of the 33 My invention further comprises the appaline, and with motors operating on high-poratus and arrangement of circuits hereinafter tential circuits it is obviously undesirable more fully described,and shown in the accomthat the controlling-circuit should be of this panying specification and drawing, in which high potential, and connections have been the figure is a diagrammatic representation devised for providing a controlling-circuit of 40 of circuits and apparatus embodying my inmuch lower potential than the main line. vention. WVith my new system the controlling-cir- While my invention is applicable to motors cuit leading to the floors or stations may be in general, I have shown it in connection with derived from any suitable source of the dea motor operating an elevator, and referring sired low potential; but in this instance the 5 to the drawing, A represents a suitable mocontrolling-circuit is shown deriving its en- 5 tor, shown in this instance as an electric moergy from a separate source from the main tor driving a sheave B, connected to operate line, as a battery E of lower potential than a car or cage 0 by a suitable cable D, (shown the mains, which are indicated in the diagram in part broken away for the sake of clearby the and signs. According to my in- 50 ness,) while I Y Y Y represent floors or vention the low-potential circuit is first onergized by the operation of a push-button or switch at a station or on the car, and the circuits and connections between the push-buttons and the motor are such that the motor is started to bring the car to the desired station; but as the motor starts the low-potential controlling-circuit is rendered inoperative by being in this instance denergized, and it remains in this condition during the operation of the motor, thereby rendering all of the push-buttons or switches inoperative to prevent interference during the operation of the motor.

In the drawing, the low-potential controlling-circuit leading to the floors or stations and in this instance shown as also leading to the car is represented by continuous heavy lines, while the main motor-circuit is represented by heavy dotted lines, and the continuous light lines represent other controlling-circuits for the motor connected to suitable controlling apparatus, as a floor-controller, for automatically stopping the car or cage at the desired station, and also including electroreceptive devices, as solenoids, for operating a suitable reversing-switch for the motor.

The controllingcircuits (represented by light continuous lines in the diagram) are shown in this instance as connected in a shunt to the main motor-circuit,therebyderiving energy from the main line, and the electric potential of these motor-controlling circuits is substantially that of the line, and, as hereinafter to be described, this shunt controlling-circuit includes the door-contacts or door-switches, one for each landing, operated by the opening and closing of the well-doors, and also includes a safety-switch on the car, and it may include a car-gate switch, since switches of any suitable character for breaking a highpotential circuit may be readily provided at these points where small push-buttons and light contacts would be inapplicablein a highpotential circuit. By then combining the push-button circuit of low potential and the remainder of the controllingcircuits of a higher potential in the manner to be described it will be hereinafter seen that these circuits reciprocally control each other when the motor is to be operated.

A suitable reversing-switch for the motor is represented diagrammatically at F, there being four sets of contacts 1 2 3 4, as shown, the individual movable contacts of which (indicated for sake of simplicity as carried by armatures 5 6 7 8) being adapted to be moved with their armatures and closecontact with the oppositely lying separated contacts. When armatures 5 and 6 are moved in a direction to close circuit between the contacts they carry and their oppositely-lying contacts, the circuit of the motor will be closed in a manner to cause the armature to rotate in one direction, while when the armatures '7 S are moved in a like manner the armatureone shown, providing it accomplishes the de- 7 sired result.

Assuming groups 3 and 4 of the contacts 011 the reversing-switch F to be closed and magnet U maintaining its contacts closed, thereby completing a circuit from the positive main to the reversing-switch F, the circuit of the motor will be closed as follows: Current entering the reversing-switch by the positive lead passes, first, through the right-hand pair of contacts 3 and then through the left-hand pair of contacts at, and from thence through the left-hand pair of contacts 3 to and through the armature of the motor, from thence through the right-hand pair of contacts lto and through the armature resistance 40, through series field-winding 41, and to the negative lead, thereby completing the circuit to the motor and its shunt field 42. Should the groups 5 and 6 of the contacts on the reversing-switch F be closed, a similar circuit for the motor may be traced out; but the current will pass through the motor-armatu re in a reverse direction.

The operation of the solenoids U and D is controlled from the floors or stations and from the car through a suitable floor-controller or automatic means for stopping the motor when the car has arrived at its destination. The floor-controller (represented by G) may be of any suitable character, but is preferably of the kind shown and described in my prior application referred to, Serial No. 660,873, in which there is a drum or disk 14-, adapted to be rotated by the motor in any suitable manner in unison with the travel of the car. Upon the periphery of the disk 14 are arranged segments 15 1G, insulated from each other at 17 18 and arranged with contacts or brushes 19, hearing thereon, connected in one portion of the controlling-circuit, while the contacts 20 and 21 are connected, respectively, to the solenoids D and U.

For operating the reversing-switch F it is understood that when the solenoid D is energized the reversingswitch is caused to complete the armature-circuit in such a manner that the motor will rotate in a direction to cause the car to descend, and when the solenoid U is energized the motor is caused to rotate in the opposite direction to cause the car to ascend.

The circuits of the solenoids D and U are adapted to be broken at the floor-controller G by the insulation 17 18 in a manner hereinafter to be described to stop the car automatically at its desired destination.

Other segments CL Z) are shown on the drum or disk 14 of the flo0r-controller G insulated from each other at the points 0 (Z opposite the insulation 17 18 on the disk, but each provided with a conducting portion e f, extending in close proximity [to but insulated from the ends of the segments 15 16, as shown, so that as the disk 14 moves in unison with the travel of the car in one direction or the other before the controlling-circuit can be broken completely an additional circuit must be made through brushes g 72, bearing on the segments a b, and through electroreceptive devices, shown as solenoids 2' 75, adapted to operate a switch l, controlling a resistance in shunt to the armature of the motor this resistance being shown as an extra shunt fieldwinding m. When the switch Zis closed, this extra .field winding becomes energized, strengthens the field of the motor, and slows down the armature, and this operation takes place at a predetermined point in the travel of the car controlled by the floor-controller, so that the rate of travel of the car is changed and, as described, slowed down at a predetermined point and for an appreciable length of time before the car is stopped.

Let it be assumed that the car 0 is near the limit of its downward travel and that it is desired to bring it to the upper station Y If the door-contacts T at all of the stations and the safety-switch S on the car are all closed, then by manipulating a push-button P at the floor Y a circuit will be closed as follows: from the terminal of the battery E, through the normally closed contacts controlled by an electromagnet H, thence through the normally closed contacts I, controlled by an accelerating-magnet 4L3,which cuts out the armature-resistance and series field as the motor comes up to speed, from thence by wire 22 to one side of the push-buttons P at the floors or stations connected in parallel with each other and in parallel with those 011 the car, thence through the button manipulated at the station Y and by a wire 23 through the winding 3 of one of the series of doublywound electromagnets WV, thence through the winding 0" on the doubly-wound electromagnot B and to the terminal of the battery E. By the closure of the low-potential controlling-circuit as described the winding 2* of magnet R becomes energized, and the normally open contacts at this magnet are closed thereby, while the energizing of the winding 8 of one of the doubly-wound magnets YV attracts one of the contacts 6 against the core of the magnet W. The closure of these sets of contacts completes a controlling-circuit derived from the main line as follows: from the point 24 on the positive main, through the winding 1' of magnet R to the core of the same, and thence through the contacts previously closed and by wire 25 through the door-contacts T, by flexible cable V to safety-switch S on the car, back by flexible cable V, and from thence, still by wire 25, to and through the winding of electromagnet H, thence by a wire 6 to a contact t, which has been attracted against the core of the magnet XV, and from said core current passes through the winding 8' of the magnet W, from thence to the brush 19 of the floor-controller G, and the '[ioor controller being in the position shown current passes from brush 21 by a wire 26 to a stop-motion switch K, shown in the form of an insulating-disk 60, carrying series of segmental contacts arranged radially thereon, while there are other cooperating contacts provided, as at 28 and 32, and suitable means for moving the contacts on the diskand their cooperating contacts with relation to each other for controlling the circuits leading to the stop-motion switch. This relative movement of the contacts may be controlled by a suitable connection with the motor itself, so that the switch moves in unison with the travel of the car to break the motor-controlling circuits at the extreme limits of the upward and downward travel of the car, or it may be simply a hand-switch for use in case of emergency. The stop-motion switch K, as stated, is in the nature of an emergency switch and is designed to break the motor-controlling circuits and stop the motor if for any reason the car exceeds the normal limit of its travel in either direction. To stop the motor with this switch for a given direction of rotation of the motor, contact must be broken between the segmental contacts and their cooperating contacts, as 28 and 32, and for the opposite rotation of the motor contact would be broken at the other side of the stop-motion switch K. The pieces and 71 are not in this instance connected to circuit-wires and merely form rests for one or the other of the sets of contacts cooperating with the segmental contacts when the circuit is broken at the stop-motion switch. In any event the construction and operation of this switch forms no part of my present invention and will not be described further than to trace the circuits as follows: As stated, current entering the switch by wire 26 will pass to contact 27 and by contact 28 to @011- tact 29, and from thence by wire 30 to and through solenoid U, through another solenoid U back by wire 30 to contact 31 on the stopmotion switch to contact 32, and from contact by wire 34 to limit-switches 35, and by wire 26 to the negative main at 37. Current enterin g the switch by wire 72 will pass through connections to the other side of the switch, said connections being similar to those illustrated and described, and in this case magnet D will be energized. Suitable resistances 38 and 39 are included in this derived controlling circuit for reducing the current therein.

The energizing of the winding of electromagnet H by the closure of the shunt controlling-circuit described immediately opens the normally closed contacts of this magnet, thereby breaking the low-potential circuit deriving its energy from the battery E, and since, as described, all of the buttons on the car and at the stations derive their energy from this battery it will be seen that interference with the operation of the motor from the floor or station or from the car 0 while the motor is in operation is prevented. Additional means of preventing interference are provided in the normally closed contacts I I, controlled by the accelerating-magnet 43, which cuts out the armature resistance in the series field on the starting, for these contacts I I are also opened as the motor starts. As shown in this instance, the contact I is connected to move with, but is insulated from, movable contact 44, so that as contact 44 is attracted by its magnet-core the contacts I I will be opened.

The energizing of the winding 8 on the magnet W maintains the same magnetized, and therefore continues to attract the contacts 6 against said core. After the low-potential controlling-circuit is broken and the winding 3 deenergized the same operation takes place at the-doubly-wound magnet R, where the winding r is denergized when the low-potential circuit is broken, the winding r, energized by the completion of the shunt controlling-circuit, thereby maintaining the contacts of this magnet closed.

The energizing of the solenoid U in the manner described serves to actuate the armatures 7 8 to close the motor-circuit in a manner to cause the motor to rotate in a direction to bring the car downward, while the energizing of solenoid U closes the normally open contacts which it controls in the main circuit, allowing current to pass to the reversing-switch and from thence to the motor.

\Vithout tracing all of the motor-circuits, it will be sufiicient to specify that 40 represents the armature-resistance; 41, the series field; 42, the shunt field of the motor; 43, an accelerating-magnet connected directly across the brushes of the motor in such manner that as the counter electromotive force increases this magnet acts with increasing strength and closes the normally open contacts 44 45 46 47 one after the other in the order named to gradually cut out the armaturefresistance of the series field on starting. The motor having started in the proper direction, it will continue to rotate, moving the floor-controller G in unison with the travel of the car in the direction or" the arrow; but as the brush 19, through which current is passing,reaches the end of the segment 16, with which it is in contact, which is arranged to take place as the car approaches its destination, said brush 19 passes onto the conducting portion f, connected with the segment Z2, thereby i11- cluding the solenoid 7c in the circuit of the solenoid D, closing the normally open switch Z, and energizing the extra field-winding m, thereby increasing the field strength of the motor and slowing down the armature for the length of time that the brush 19 remains on the conducting portion f of the floor-controller, the controlling-circuit being completely broken when the insulation 17 comes opposite brush 19, in which case the solenoids U and U become denergized and break the armature-circuits. It will thus be seen that the low-potential controlling-circuit, including the push-buttons or their equivalents, is automatically cut out or rendered inoperative after having been energized to start the motor; but this low-potential circuit only remains inoperative temporarily or during the operation of the motor, for as soon as the circuit of one of the up or down relays is broken or proper circuit is broken the parts of the controlling apparatus are restored to normal position and the low-potential circuit is in readiness to be again energized upon manipulation of the push-button.

The push-button circuit is preferably derived from a separate source from that which supplies the motor with current, and by the operation of the apparatus as described this separate source of low potential supplying the push-button circuit with current is put out of circuit as the motor starts and is maintained out of circuit as long as the motor is in operation. The push buttons, switches, or their equivalents at the floors or stations and on the car, one of which when manipulated sets the motor in operation, may be said to be means controlling the starting of the motor or for starting the car to a particular station.

The motor is provided with controlling devices, as devices for determining the direction of rotation of the motor and the time during which it operates after having been started, while there are means included in a circuit of lower potential than the main circuit for controlling the operation of these controlling devices. As shown, there are circuits derived from the main circuit for the motor-controlling devices, and these circuits do not include the push-buttons at the floors and on the car, but at the floors only include safety-switches as door-contacts and on the car only include a safety-switch.

From the arrangement of controlling-circuits described it may be said that according to my invention there are circuits and connections including the push buttons or switches and the devices for controlling the operation of the motor and that of these circuits that portion including the switches is of lower potential than the remainder of the circuits.

According to my invention the door contacts or switches at the floors, as stated, are not included in the low-potential push-button circuit, and I provide means for rendering the low-potential push-button circuit inoperative after a button has been manipulated, while maintaining the door contacts or switches at the stations operative after one of the push-buttons is manipulated.

The circuit including the motor-controlling devices and the circuit of lower potential, including the push-buttons at the landings and on the car, are so arranged that they are interacting, or, in other words, they reciprocally comes? control each other, for when a push-button is manipulated-the circuit of the push-buttons operates to close the circuit of the motor-controlling devices, while said latter circuit upon becoming energized opens the circuit of the push-buttons and prevents interference with the operation of the motor.

It has been seen that the controllingcircuit, including the motor-controlling devices, also includes safety-switches, as door-contacts, at the floors and a safety-switch on the car, While'there are other switches at the floors, as embodied in the push-buttons included in a circuit of lower potential than the circuit including said controlling devices.

Without limiting myself to the precise construction and arrangement of parts shown, I claim as my invention 1. In a motor-controlling apparatus, the combination of controlling-circuits of diiterent potentials reciprocally controlling each other, substantially as described.

2. In an apparatus for controlling elevators, the combination of two controlling-circuits of different potentials reciprocally controlling each other, substantially as described.

3. In a motor-controlling apparatus, the combination of controlling-circuits reciprocally controlling each other and derived fro m different sources, substantially as described.

4. In a motor-controlling apparatus, the combination of controlling-circuits reciprocally controlling each other and derived from separate sources of different potentials, substantially as described.

5. In an electrical controlling system for elevators, the combination with a motor, and car, of a main motor-circuit, a controlling-circuit of lower potential than said main circuit, and means for momentarily energizing the lowpotential circuit to start the car and for then rendering said low-potential circuit inoperative, substantially as described.

6. The combination with an electric motor, and its main circuit, 'of a controlling-circuit of lower potential than the main circuit, and means for rendering said controlling-circuit inoperative after the motor is started, substantially as described.

7. The combination with an electric motor, and its main circuit, of a controlling-circuit of lower potential than the main circuit, and means for rendering said controlling-circuit temporarily inoperative after the motor is started, substantially as described.

8. The combination with an electric motor, and its main circuit, of a controlling-circuit of lower potential than the main circuit, and means for maintaining said controllingcircuit inoperative while the motor is in operation, substantially as described.

9. The combination with an electric motor, and its main circuit, of a controlling-circuit of lower potential than the main circuit, and means for cutting out said controlling-circuit as the motor starts,substantially as described.

10. In an electrical controlling system for elevators, the combination with a motor and its main circuit, of a controlling-circuit derived from a separate source of lower potential than the main circuit, and means for cutting out said separate source as the motor starts, substantially as described.

11. In an elevator, the combination with a motor, car, and stations, of a main circuit for the motor, and means at the stations included in a circuit of lower potential than said main circuit for controlling the operation of the motor, substantially as described.

12. In an elevator, the combination with a motor, car, and stations, of a main circuit for the motor, and means on the car included in a circuit of lower potential than said main circuit for controlling the operation of the motor, substantially as described.

13. In an elevator, the combination with a motor, car, and stations, of a main circuit for the motor, and means on the car and at the stations included in a circuit of lower potential than said main circuit for controlling the operation of the motor, substantially as described.

14. In an electrical controlling system for elevators, the combination with a motor, car, and stations, of a main circuit for the motor, a controlling-circuit of lower potential than said main circuit, and means for rendering the controlling-circuit inoperative when the motor starts, substantially as described.

15. In an electrical controlling system for elevators, the combination with a motor, car, and stations, of a main circuit for the motor, a controlling-circuit of lower potential than said main circuit, and means for rendering the controlling-circuit inoperative after having been energized,substantially as described.

16. In an electrical controlling system for elevators, the combination with a motor, car, and stations, of a main circuit for the motor, a controlling-circuit of lower potential than said main circuit, means at the stations included in said controlling-circuit for controlling the starting of the motor, and means for rendering said controlling-circuit inoperative after the motor has started, substantially as described.

17. In an electrical controlling system for elevators, the combination with a motor, car, and stations, of a main circuit for the motor, a controlling-circuit of lower potential than said main circuit, means on the car included in said controlling-circuit for controlling the starting of the motor, and means for rendering said controlling-circuit inoperative after the motor has started, substantially as described.

18. In an electrical controlling system for elevators, the combination with a motor, car, and stations, of a main circuit for the motor, a controlling-circuit of lower potential than said main circuit, means on the car and at the stations included in said controlling-circuit for controlling the starting of the motor,

and means for rendering said controlling-circuit inoperative after the motor has started, substantially as described.

19. In an elevator, the combination with a motor, and its main circuit, of means controlling the starting of the motor included in a circuit of lower potential than said main circuit, and means for rendering said low-potential circuit inoperative after the motor has started, substantially as described.

20. In an elevator, the combination with a motor, car, stations, and main circuit of the motor, of means included in a circuit oflower potential than said main circuit for starting the car to a particular station, and means for rendering said starting means inoperative after once being operated, substantially as described.

21. In an elevator, the combination with a motor, car, stations, and main circuit of the motor, of means included in a circuit of lower potential than said main circuit for starting the car to a particular station, and means for rendering said starting means temporarily inoperative after once being operated, substantially as described.

22. In an apparatus for controlling eleva tore, the combination with a motor, car, and stations, main circuit of the motor, and controlling devices, of means included in a circuit of lower potential than said main circuit for controlling said controlling devices and starting the car to a particular station, and means for rendering said circuit of low potential inoperative after having started the car, substantially as described.

23. In an electrical controlling system for elevators, the combination with a motor, its main circuit, controlling devices, and circuits therefor, of means included in a circuit of lower potential and derived from a different source than the main circuit for controlling said controlling devices, substantially as described.

2a. In an electrical controlling system for elevators, the combination with a motor, its main circuit, controlling devices and circuits therefor, of means included in a circuit of lower potential than the main circuit for controlling said controlling devices, and means for rendering said circuit of low potential temporarily inoperative after having once been energized, substantially as described.

25. In an apparatus for controlling elevators, the combination with a motor, and its main circuit, of motor-controlling devices and circuits therefor, and a circuit of lower potential than the main circuit and derived from a separate source controlling the operation of said controlling devices and their circuits, substantially as described.

26. In an apparatus for controlling elevators, the combination with a motor, and its main circuit, of motor-controlling devices and circuits for the same derived from said main circuit, and a circuit of lower potential than said main circuit derived from a separate source for controlling the operation of said controlling devices and their circuits, substantially as described.

27. The combination with an elevator-motor, of switches, circuits and connections including the switches and motor for controlling the operation of the motor, the portion of said circuits including the switches being of lower potential than the remainder of the circuits, and means for cutting said portion of low potential out of circuit after the motor is started, substantially as described.

28. The combination with an elevator-m0- tor, of switches, circuits and connections including the switches and motor for controlling the operation of the motor, the portion of said circuits including the switches being of lower potential than the remainder of the circuits, and means for automatically cutting said portion of low potential out of circuit as the motor starts, substantially as described.

29. The combination with an elevator-motor, of switches, circuits and connections including the switches and motor for controlling the operation of the motor, the portion of said circuits including the switches being of lower potential than the remainder of the circuits, and means for automatically cutting said portion of low potential out of circuit when one of said switches is operated, substantially as described.

30. In an apparatus for controlling elevators, the combination with a motor, car, and stations, of push-buttons and switches for each station, controlling-circuits and connections between the push-buttons and motor for controlling the operation of the motor, the portion of said circuits including the pushbuttons being of lower potential than the remainder of the circuits, and means for automatically rendering the push-buttons inoperative while maintaining the switches at the stations operative after one of the push-buttons is n'ianipulated, substantially as described.

Sl. In an apparatus for controlling elevators, the combination with a motor, car, and stations, of a circuit including switches for setting the motor in operation, and a circuit including motor-controlling devices, said circuits being so arranged as to reciprocally control each other, substantially as described.

In an apparatus for controlling elevators, the combination with an electric motor, of a circuit including switches for setting the motor in operation, and a separate circuit including motor-controlling devices and derived t'rom a separate source, said circuits being so arranged as to reciprocally control each other when one of said switches is operated, substantially as described.

33. In an apparatus for controlling elcvators, the combination with a motor, car, and stations, of a circuit including switches for setting the motor in operation, and a circuit including motor-controlling devices, said circuits being so arranged that when a switch is manipulated the circuit of the switches closes the circuit of the motor-controlling devices and said latter circuit opens the circuit of the switches, substantially as described.

34. In an apparatus for controlling elevators, the combination with a motor, car, and stations, of a circuitincluding motor-controlling devices, and a circuit of lower potential than the same including switches for setting the motor in operation, said circuits being so arranged as to reciprocally control each other, substantially as described.

35. In an apparatus for controlling elevators, the combination with a motor, car, and stations, of a circuit including motor-controlling devices, and a circuit of lower potential than the same including switches for setting .the motor in operation, said circuits being so arranged that when a switch is manipulated the circuit of the switches closes the circuit of the motor-controlling devices and said latter circuit opens the circuit of the switches, substantially as described.

36. In an apparatus for controlling elevators, the combination with a motor, car, stations, and main motor-circuit, of motor-controlling devices, a circuit including the same derived from the main circuit, switches for setting the motor in operation, and a circuit including the same derived from a separate source of lower potential than the main circuit, said circuits including the motor-com trolling devices and switches being so arranged as to reciprocally control each other, substantially as described.

37. In an apparatus for controlling elevators, the combination with a motor, car, stations, and main motor-circuit, of motor-controlling devices, a circuit including the same derived from the main circuit, switches for setting the motor in operation, and a circuit including the same derived from a separate source than the main circuit, said circuits including the motor -controlling devices and switches being so arranged as to reciprocally control each other,substantially as described.

38. In an apparatus for controlling elevators, the combination with a motor, car, stations, and main motor-circuit, of push-buttons at each station for setting the motor in operation, a circuit including the same, and a circuit including door-switches at the stations and also including devices for controlling the motor, said circuits being so arranged as to reciprocally control each other, substantially as described.

39. In an apparatus for controlling elevators, the combination with a motor, car, stations, and main motor-circuit, of push-buttons on the car for setting the motor in operation, a circuit including the same, and a circuit including door-switches at the stations and also including devices for controlling the motor, said circuits being so arranged as to reciprocally control each other, substantially as described.

40. In an apparatus for controlling eleva i tors, the combination with a motor, car, stations, and main motor-circuit, of push-buttons on the car and at the stations for setting the motor in operation, a circuit including the same, and a circuit including door-switches at the stations and also including devices for controlling the motor, said circuits being so arranged as to reciprocally control each other, substantially as described.

al. In an apparatus for controlling elevators, the combination with a motor, car, stations, and main motor-circuit, of switches at each station for setting said motor in operation, a circuit including the same, and a circuit including other switches at the stations and also including devices for controlling the motor, said circuits being so arranged as to reciprocally control each other, substantially as described.

42. In an apparatus for controlling elevators, the combination with a motor, car, stations, and main motor-circuit, of switches on the car for setting the motor in operation, a circuit including the same, and a circuit including switches at the stations and also including devices for controlling the motor,said circuits being so arranged as to reciprocally control each other, substantially as described.

43. In an apparatus for controlling elevators, the combination with a motor, car, stations, and main motor-circuit, of switches on the car and at the stations for setting the motor in operation, a circuit including the same, and a circuit including other switches at the stations and also including devices for controlling the motor, said circuits being so arranged as to reciprocally control each other, substantially as described.

at. In an apparatus for controlling elevators, the combination with a motor, car, sta tions, and main motor-circuit, of circuits including door-switches at the stations and also devices for controlling the motor, push-buttons at each station for setting the motor in operation, and a circuit including the same of lower potential than the circuit including the door-switches and motor-controlling devices, said circuits of different potentials bein so arranged as to reciprocally control each other, substantially as described.

45. In an apparatus for controlling elevators, the combination with a motor, car, stations, and main motor-circuit, of circuits including door-switches at the stations andalso devices for controlling the motor, push-buttons on the car and at the stations for setting the motor in operation, and a circuit including the same of lower potential than the circuit including the door-switches and motorcontrolling devices, said circuits of different potentials being so arranged as to reciprocally control each other, substantially as described.

46. In an apparatus for controlling elevators, the combination with a motor, car, stations, and main motor-circuit, of a circuit including switches at the stations and also in cluding devices for controlling the motor, other switches at each station for setting the motor in operation, and a circuit including the same of lower potential than the circuit including the motor-controlling devices, said circuits of different potentials being so arranged as to reciprocally control each other, substantially as described.

47. In an apparatus for controlling elevators, the combination with a motor, car, stations, and main motor-circuit, of a circuit including switches on the car and also including devices for controlling the motor, and a circuit of lower potential than the same, said circuits being so arranged as to reciprocally control each other, substantially as described.

48. In an apparatus for controlling elevators, the combination with a motor, car, stations, and main motor-circuit, of push-buttons for each station and a circuit including the same, and motor-controlling devices and a circuit including the same, said circuits being so arranged as to reciprocally control each other, substantially as described.

49. In an apparatus for controlling elevators, the combination with a motor, car, stations, and main motor-circuit, of push-buttons for each station and a circuit including the same, and motor-controlling devices and a circuit including the same, said circuits acting reciprocally upon each other, substantially as described.

50. In an apparatus for controlling elevators, the combination with a motor, car, stations, and main motor-circuit, of push-buttons for each station and a circuit including the same, and motor-controlling devices and a circuit including the same, said circuits being so arranged that when a push-button is manipulated the push-button circuit closes the circuit of the motor-controlling devices, and said latter circuit opens the circuit of the push-buttons, substantially as described.

51. In an apparatus for controlling elevators, the combination with a motor, car, stations, and main motor-circuit, of push-buttons for each station and a circuit including the same, motor-controlling devices and a circuit including the same, and means in the push-button circuit for closing the circuit of the motor-controlling devices when a pushbutton is manipulated, substantially as described.

52. In an apparatus for controlling elevators, the combination with a motor, car, stations, and main motor-circuit, of push-buttons for each station and a circuit including the same, motor-controlling devices and a circuit including the same, means in the pushbutton circuit for closing the circuit of the motor-controlling devices when a push-button is manipulated, and means in said latter circuit for opening the circuit of the pushbuttons, substantially as described.

53. In an apparatus for controlling eleva tors, the combination with a motor, car, stations, and main motor-circuit, of motor-con- 7 trolling devices and a circuit including the l same, push-buttons for each station, and a circuit including the same of lower potential than the circuit including the motor-controlling devices, said circuits being so arranged as to reciprocally control each other, substantially as described.

54. In an apparatus for controlling elevators, the combination with a motor, car, stations, and main motor-circuit, of motor-controlling devices and a circuit including the same, push-buttons for each station, and a circuit including the same of lower potential than the circuit including the motor-controlling devices, said circuits acting reciprocally upon each other, substantially as described.

55. In an apparatus for controlling elevators, the combination with a motor, car, stations, and main motor-circuit, of motor-controlling devices and a circuit including the same, push-buttons for each station, and a circuit including the same of lower potential than the circuit including the motor-controlling devices, said circuits being so arranged that when a push-button is manipulated the push-button circuit closes the circuit of the motor-controlling devices and said latter circuit opens the circuit of the push-buttons, substantially as described.

56. In an apparatus for controlling elevators, the combination with a motor, car, stations, and main motor-circuit, of motor-controlling devices and a circuit including the same, push-buttons for each station and a circuit including the same of lower potential than the circuit including the motor-controlling devices, and means in the push-button circuit for closing the circuit of the motorcontrolling devices when a push-button is manipulated, substantially as described.

57. In an apparatus for controlling elevators, the combination with a motor, car, stations, and main motor-circuit, of motor-controlling devices and a circuit including the same, push-buttons for each station and a circuit including the same of lower potential than the circuit including the motor-controlling devices, means in the push-button circuit for closing the circuit of the motor-controlling devices when a push-button is manipulated, and means in said latter circuit for opening the circuit of the push-buttons, substantially as described.

58. In an apparatus for controlling elevators, the combination with a motor, car, stations, and main circuit of the motor, of a circuit derived from the main circuit and including motor-controlling devices, switches at the stations for setting the motor in operation, and a circuit including the same derived from a separate source of lower potential than the main circuit, said circuits derived from the main circuit and the separate source being so arranged as to reciprocally control each other, substantially as described.

59. In an apparatus for controlling elevators, the combination with a motor, car, and

circuit including the same, switches for set ting the motor in operation and a circuit including the same, means in the circuit of said switches for closing the circuit of the motorcontrolling devices, and means in the circuit of the motor-controlling devices for maintaining the circuit of the same closed, substantially as described 61. In an apparatus for controlling elevators, the combination with a motor, and its main circuit, of two motor-controllin g circuits one including switches for starting the motor and adapted to be opened when the motor is in operation and the other including motorcontrolling devices, means in the circuit of said switches for closing the circuit of the motor controlling devices, and means in the circuit of the motor-controlling devices for maintaining the circuit of the same closed while the motor is in operation, substantially as described.

In testimony whereof I have signed my name to this specification in the presence of two subscribing witnesses.

JOHN D. IHLDER.

Witnesses:

CHARLES B. MANVILLE, F. W. NEWELL. 

